Core A takes care of the tissue processing needs for all projects. It is directly supervised by Dr. Pelayo Correa. In New Orleans our personnel receives all biopsies in the endoscopy suits. Biopsies for histopathology evaluation are fixed immediately in buffered zinc-formalin, embedded in paraffin, sectioned and stained with hematoxylin eosin and modified Warthin- Starry silver stain. Biopsies for frozen sections are received in OCT and frozen immediately. The laboratory performs all immunohistochemical stains, including Ki67, TUNEL assays, inducible nitric oxide synthase, nitrotyrosine and a variety of white blood cell markers. Tissue selected for in situ hybridization will utilize frozen sections. The laboratories are located in the Department of Pathology. Fully trained and experienced personnel are available for all procedures. From Colombia, the laboratory receives paraffin blocks and frozen tissue for processing as described.